Financing (Narrative) (Details) (USD $)	12 Months Ended
	Sep. 29, 2012	Oct. 01, 2011
Line of Credit Facility [Line Items]
Bank line of credit facility, amount outstanding		$ 40,000,000
Letters of credit outstanding, amount	19,100,000
Line of credit facility, interest rate at period end (in hundredths)	0.70%	0.70%
Effective interest rate applicable to outstanding credit facility (in hundredths)		2.92%
Debt interest rate spread	45.00%
Commitment fees incurred on credit facility	100,000	100,000
Guarantees outstanding, amount	30,500,000
Minimum [Member]
Line of Credit Facility [Line Items]
Line of credit facility, commitment fees payable, percent	0.15%
Maximum [Member]
Line of Credit Facility [Line Items]
Line of credit facility, commitment fees payable, percent	0.30%
Credit Facility [Member]
Line of Credit Facility [Line Items]
Bank line of credit facility, amount outstanding		75,000,000
Letters of credit outstanding, amount	10,100,000	11,300,000
Line of credit facility, remaining borrowing capacity	89,900,000	23,700,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility, expiration date	Sep. 28, 2017
Line of credit facility, borrowing capacity	$ 100,000,000
Credit facility agreement term, in years	5 years
Credit Agreement Interest Rate Scenario One [Member]
Line of Credit Facility [Line Items]
Percent added to federal funds effective rate	0.50%
Credit Agreement Interest Rate Scenario Two [Member]
Line of Credit Facility [Line Items]
Percent added to Adjusted LIBOR rate for one month interest period	1.00%
London Interbank Offering Rate [Member]
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	0.36%
London Interbank Offering Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt interest rate spread	0.875%
London Interbank Offering Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt interest rate spread	1.50%
Alternate Base Rate [Member]
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	3.25%
Alternate Base Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt interest rate spread	0.00%
Alternate Base Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt interest rate spread	0.50%